sysdeps/x86_64/dl-hwcaps-subdirs.c

   1 /* Architecture-specific glibc-hwcaps subdirectories.  x86 version.
   2    Copyright (C) 2020-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <dl-hwcaps.h>
  20 #include <cpu-features.h>
  21 #include <ldsodefs.h>
  22 #include <get-isa-level.h>
  23
  24 const char _dl_hwcaps_subdirs[] = "x86-64-v4:x86-64-v3:x86-64-v2";
  25 enum { subdirs_count = 3 }; /* Number of components in _dl_hwcaps_subdirs.  */
  26
  27 uint32_t
  28 _dl_hwcaps_subdirs_active (void)
  29 {
  30   const struct cpu_features *cpu_features = __get_cpu_features ();
  31   unsigned int isa_level = get_isa_level (cpu_features);
  32   int active = 0;
  33
  34   /* Test in reverse preference order.  */
  35
  36   /* x86-64-v2.  */
  37   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V2))
  38     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
  39   ++active;
  40
  41   /* x86-64-v3.  */
  42   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V3))
  43     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
  44   ++active;
  45
  46   /* x86-64-v4.  */
  47   if (!(isa_level & GNU_PROPERTY_X86_ISA_1_V4))
  48     return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
  49   ++active;
  50
  51   return _dl_hwcaps_subdirs_build_bitmask (subdirs_count, active);
  52 }